/*
 * Copyright (c) 2023, 2023, Oracle and/or its affiliates. All rights reserved.
 * Copyright (c) 2023, 2023, BELLSOFT. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation. Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#ifdef __linux__

#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

/*
 * Based on os::Linux::gettid() from jdk-20-ga, see
 * https://github.com/openjdk/jdk20/blob/82749901b1497f524e53e47c45708c8e4a63c8b9/src/hotspot/os/linux/os_linux.cpp#L361
 *
 * syscall() uses varargs, so we can't use @CFunction.
 */
pid_t getThreadId() {
  return (pid_t)syscall(SYS_gettid);
}

#endif

